This is a response on the problem with people's Google Checkout Images NOT appearing when they select sandbox mode:

1) You MUST sign up for a customer and merchant account on sandbox, here:
[FONT=monospace]
http://sandbox.google.com/checkout/sell/

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2) If you have NOT ran the install script for googlecheckout:

To fix your button, you must change in line 200 in your includes\modules\payment\googlecheckout.php

everywhere it says "https://sandbox.google.com/" change this to "https://sandbox.google.com/checkout/"

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3) If you HAVE ran the install script for googlecheckout, you must modify your MySQL database.

Go to PHPmyadmin for your SQL database, select your zencart database (mine is called "_zc1").

Scroll down to zen_configuration and click it.

click SQL tab, then put the following into the form and click go:

[/FONT]UPDATE `zen_configuration` SET `configuration_value` = 'https://sandbox.google.com/checkout/' WHERE `zen_configuration`.`configuration_value`="https://sandbox.google.com/" LIMIT 1 ;

and if that succeed's, proceed with:

UPDATE `zen_configuration` SET `set_function` = 'zen_cfg_select_option(array(''https://sandbox.google.com/checkout/'', ''https://checkout.google.com/''),' WHERE `zen_configuration`.`configuration_value`="https://sandbox.google.com/checkout/" LIMIT 1 ;

Your sandbox image and link is now fixed.

Anticide